Is the ocean crust as simple and regular as the conventional plate tectonics model would have us believe.
Expansion theory spreading the ocean floor.
Explaining the young age of the ocean.
This idea played a pivotal role in the development of the theory of plate tectonics which revolutionized geologic thought during the last quarter of the 20th century.
The theory of seafloor spreading.
What do we really know about seafloor spreading and how ocean crust is generated at the earth s mid ocean ridges.
The mid atlantic ridge for instance separates the north american plate from the eurasian plate and the south american plate from the african plate the east pacific rise is a mid ocean ridge that runs through the eastern pacific ocean and separates the pacific plate from the north american.
As upwelling of magma continues the plates continue to diverge a process known as seafloor spreading samples collected from the ocean floor show that the age of oceanic crust increases with distance from the spreading centre important evidence in favour of this process.
Conversely geophysical global cooling was the hypothesis that various features could be explained by earth contracting.
This theory introduced by harry hess was proven as patterns of magnetic.
The expanding earth or growing earth hypothesis asserts that the position and relative movement of continents is at least partially due to the volume of earth increasing.
Detailed research of the ocean configuration was done using sonic waves and it contained a sender and a receiver.
Seafloor spreading theory that oceanic crust forms along submarine mountain zones known collectively as the mid ocean ridge system and spreads out laterally away from them.
Seafloor spreading is the mechanism by which new seafloor lithosphere is constantly being created at mid ocean ridges.
To map the oceanic floor provided a detailed picture of the ocean relief.
Earth expansion advocates fixated on this observation.
The strange fact that the ocean floor is billions of years younger than the earth s land.
Spreading rates determine if the ridge is fast intermediate or slow.
Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor.
What actually is the moho seismic horizon beneath the ocean floor long taken as the boundary between crust and the mantle.
Spreading rate is the rate at which an ocean basin widens due to seafloor spreading.
Although it was suggested historically since the recognition of plate tectonics in the 1970s.
Seafloor spreading theory mapping of the ocean floor.
These age data also allow the rate of seafloor spreading to be determined and they show that rates.